Supercharger drive



Dec. 7, 1937. RCHMON 2,101,239

-SUFERCH ARGER DR IVE Filed Aug. 14, 1934 1 ZSheets-Sheet l INVENTOR Rom/7a Chilton.

ATTORNEY De c. 7, 1937 R. CHILTON SUPERCHARGER DRIVE Filed Aug. 14, 1934 2 Sheets-Skeet 2 VENTOR 671111012 IN Rolarrd Patented Dec. 7, 1937 SUPEROHARGER DRIVE Roland Chilton, Ridgewood, N. J., assignor, by mesne assignments, to The Reed Propeller 00.,

Inc., Garden City, N. York Application August 14,

7 Claims.

This invention relates to multiple speed super: charger drives, and in certainrespects comprises Serial No. 680,495. a

The object ofsupercharging in aircraft engines is to make up for the deficiency in atmospheric density at altitude and, by use of a sufficiently high gear ratio in the supercharger drive, normal sea level 'power may be maintained to relatively high altitudes. Engines with-such superchargers, however, would be dama ed if operated at full throttle at sea level because of the excessive power developed. Throttle stops are accordingly used and the pilot is instructed not to I pass the stop until a specified altitude is reached.

Under such part throttle conditions there is little reduction in either the power required to drive the supercharger or in the temperature rise impressed on the inlet charge by the supercharger, and both these factors combine to enforce a relatively low sea level rating on altitude supercharged engines.

I After take-oil? and climb, engines are cruised at reduced outputs usually amounting to 75% of the-maximum sea level rating, Which output also often corresponds to the capacity of a naturally aspirated engine-that is, an engine without any superchargenat full throttle. However, under these conditions the'supercharger on 5%: or more of the engine outputwhich'is entirely proved means" for overcoming these; limitations Other objects of the j invention .arefto provideji. a; supercharger drive providing two-speed and; neutral conditions. -'By use of the neutral 'condition; the impeller is entirely disconnected from I the drive and may come to rest, whereupon the engine may becruisedat ornear full throttle, and will be saved, giving increased fuel economy and range. The heating of the charge by the supercharger will also be prevented'so that the engine will work under easier thermal conditions. 5

Another object of the invention is to provide a two-speed and neutral supercharger drive which shall be so compact as to be capable of installation'in existing engines where the design initially contemplated only a single fixed ratio drive. v

Another object of the invention is to provide a two-speed and neutral supercharger drive having a simplifiedcontrol' means and one whereinthe control efiort'by the pilot is reduced to a mere finger pressure. Other objects will be ob-' improvements upon the co-pending application,

a moderately supercharged engine will absorb,

the horse power normally lost in the supercharger Y., a corporation of New 1934, Serial No. 739,765

vious or will be pointed out :in the following description.

In the drawings: Fig. 1 is an axial section through the supercharger layshaft of this invention with the supercharger impeller shaft and the drive shaft from the engine shown in fragmentary. section;

. Fig. 2 is a transverse'section through the control valve in low gear. position; v

Fig. 3 is a transverse section through trol valve in the neutral position;

Fig. 4 is a transverse section through the control valve in the high gearrposition;

Fig. 5 is an end view showing the control lever;

and I Fig. 6 is afragmentary axial section through the conthe control valve at right angles to theplane of Fig. 1. 1

Referring first to Fig. 1, l0 designates a Portion of a hollow drive shaft extending from the engine crankshaft, around which is mounted on I bushings (oneof which is shownat [2) the hollow.

supercharger impeller shaft 14 having the pinion teeth l6. The shaft III is supported in abearing ill in the rear housing", and isfurnished with the main driving .gear 22, .here shown as integral with the shaft. This main driving gear meshes with the pinion 24, shown as integralwiththe;

annular gear 26, the-whole being free to rotate, on :v

the

The. hub: 34 supports the left] hand. end of the.

layshaftla through the-bushing 4min the housinternal splines 44, with whichare engagedteeth 52 engaging the extended'end of the. teeth of layshaft 28 onthe bushing 31L v Splined at 32 on the layshaft is the hub 34 of the impeller I 36,- ,which gear has teeth 38 meshing ingl42. The rimv of the gear 36 is provided with.

"onthe outer-clutch plates 46.* Engageable with these plates are thepistonplate 48-and the a intermediate plate 50, the latter having a spline;

the pinion 24. A spring urges the piston46 towards the retracted position shown. The- Formed on the layshaft 28' are thearms 513 equipped with journals 58 whereon are mounted for free rotation the planet pinions 66, engaged with the annular gear 26 and with the sun pinion 62 which is mounted for free layshaft on the bushing 64. Splined onto the right hand end of the extended teeth of the sun' rotation about the H2 engaging a cylinment plate I6 is secured to the drum 10, as by bolts 18.

is bored outtocomprise a cylinder engaged by the piston ring carried in a groove in the piston member 82, which has a hub 84 free to slide on the bushing 86, which is secured in the housing by a suitable flange 88 by means of studs 90 (Fig. 5). A spring 92 urges the piston member 82 away from the engaged position shown;

The fixed bushing 86 serves as a bearing sup port for the right hand end of the layshaft 28. The valve housing 94 is also secured by the bolts 90 and houses the valve 96 operable by the lever 98. The valve is provided with a central bore I32, a radial hole I34, and a cut-away portion I36 (see Figs. 2, 3 and 4). The bushing 86 is further provided with a drain hole I38 communicating with the cut-away portion I40 of the valve housing 84.

A diagonal hole H4 is drilled through the bushing 86 to communicate with the hole H6 in the valve housing 94 and with the space II8 behind the piston 82. The control lever 98 is provided with a togglespring I20 anchored to the pin I22, and the spring engages a fiat face I24 of the lever, whereby the valve is stabilized in the neutral position. Hydraulic pressure is fed to the valve 96, through the oil pressure feed passage I30 (see Fig. 6) which is suitably connected to the engine lubrication system. The hollow layshaft 28 is provided with a tubular member I00 having an enlarged head I06 and which defines the exterior annular space I'02, which conducts lubricant to the pinion journals 58 through the holes I04. The tubular member I00 has further an axial bore I I0 and a radial hole I08 by which clutch actuating oil pressure is communicated to the piston 48 when the valve 96 is turned into the appropriate position.

The operation of the device will now be clear, as follows:

The engine drives the shaft I0, equipped with the main driving gear 22, which in turn drives the pinion 24 and the annular gear 26 at all times when the engine is running. The pinion 24, however, is free on the layshaft 28 which it may drive in either of two ways(a) by engagement of the direct drive clutch plates 50 and 46, the supercharger drive gear 36 will be driven at unitary speed with the layshaft, giving high gear, during which the low gear or sun gear clutch plates 66, 68, I4, will be disengaged to permit the pinion 62 to turn .at unitary speed with the rest of the layshaft parts. (1)) If the high speed clutch 46, 50 be disengaged, and the low speed or sun pinion clutch 66, 68, I4 be engaged, as shown, then the layshaft and the supercharger drive gear 36 are driven through the planetary gears 26, 60, and the sun pinion 62 which is held locked to the housing.

It will be obvious that if both clutches be released, no drive will be transmitted to the supercharger pinion l6 so that the device will be in neutral position. v

The porting of the valve body 94 and the valve 96 is as indicated in Figs. 2', 3 and 4 repre senting respectively the low, neutral and high,

gear positions of the valve, and it will be seen that in low gear position the valve connects the The right hand end of the drum 10 high gear clutch piston 48 to the drain hole I38, at the same time supplying pressure to the low gear clutch through the hole H4 and the valve port I36. In neutral position both high and low gear pistons are put into communication with the drain hole I38, while the pressure 'is cut off both clutches. In the high gear position, pressure is communicated with the high gear clutch, through the holes I30, I34, I32, H0 and I08, while the low gear clutch is drained through I36, I40, I38. It will be clear from Figs. 2, 3 and 4, that these relations cannot be disturbed by any manipulation of the valve 98, by which either .or

neither of the clutches may be subject to engaged at moderate altitudes, and high gear at higher altitudes.

While I have described my invention in detail in its present preferred embodiment, it will be obvious to those skilled in the art, after understanding my invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. I

aim in the appended claims to cover all such modifications and changes.

What is claimed is:

1. The combination with a supercharger layshaft, of a' pinion rotationally free from said shaft, a supercharger driving gear upon said shaft, 9. sun gear rotationally free upon the shaft, an annular gear rigid with the pinion, planet pinions engaging the last said gears, a clutch means adapted to lock the sun gear against rotation, a second clutch means adapted to lock the layshaft pinion to the layshaft, and means to engage either of said clutches and adapted to disengage both.

2. In a supercharger drive in combination, a layshaft, a-pinion free for rotation on the layshaft, a clutch adapted to engage said pinion for pinion engaged with said gear and having a layshaft gearengaged with said supercharger pinion, a. planetary gearset including a sun gear between said layshaft gear and said layshaft pinion, means to selectively clutch and declutch the layshaft gear directly to the layshaft pinion, and separate means'to selectively free and restrain said sun gear as to rotation.

4. The combination with an engine having a casing, a supercharger drive gear and asupercharger pinion, of a layshaft laterally spaced from said gear and pinion thereon a gear meshed with said pinion, a pinion on said layshaft meshed with said drive gear, selectively operable means to clutch said layshaft pinion to said layshaft gear, a 'ratio changing gearset connected with said layshaft gear and with said layshaft pinion, a reaction member in said gearset,and means selectively operable to clutch axis, having mounted ion, clutch means selectively operable to clutch the said reaction member to said casing. and to tree said reaction members from restraint.

5. In a supercharger drive, in combination, a drivegear and a coaxial supercharger pinion, a layshaft having a pinion and gear respectively meshed with said drive gear and supercharger pinlayshaft pinion for rotation with the layshaft gear, a speed changing mechanism operably connected between saidlayshait pinion and said layshaft gear, selectively operable clutch means to place said speed changing mechanism in operative relationship between said layshait pinion and said layshaft gear to enforce relative rotation of said pinion and gear, and a unitary control for both said clutch means having" one position for dision'mounted for rotation on the shaft, a driving gear mounted on the shaft, selectively operable clutch means to connect the gear for rotation with the pinion, a speed changing gear set between said pinion and gear in driving connection with each, said gearset including a reaction member freely rotatable on the shaft in either direction, and a second selective clutch organized in one position of adjustment to hold said reaction member from rotation and in another position of adjustment to release said reaction member for free rotation. v

7. The combination in a supercharger drive including a drive gear, a supercharger pinion, a layshait having gears respectively engaged with the driving gear and pinion, oi a change speed gear between said layshait gears, and at least two selectively and reciprocally operable clutches for engaging the layshaft gears for direct drive, for engaging the change speed gear between the layshait gears, and for severing both of said driving engagements.

ROLAND CHILTON. 

